Obtaining tissue samples for diagnostic purposes is a commonly performed surgical procedure known as a biopsy. Such a procedure requires two steps: cutting a tissue sample and then retrieving the cut sample. Electrosurgical devices are a well known surgical instrument. Such devices cut the tissue by applying a voltage across two electrodes, creating an arc discharge which creates such a high heat energy that the cells comprising the tissue break down. Electrosurgical cutting has been utilized on catheters for a less invasive procedure such as shown in U.S. Pat. No. 4,976,711 to Parins et al.
The prior art has shown various ways to retrieve the cut tissue. U.S. Pat. No. 4,655,216 to Tischer utilizes an open ended basket. U.S. Pat. No. 4,953,559 to Salerno utilizes a cup shaped forceps on the end of a linkage arm.
What is needed is a biopsy device which is minimally invasive by utilizing electric surgical cutting and coagulating and a means to retrieve the cut tissue sample without the complicated linkage arms.
Therefore the primary object of the present invention is to provide a bipolar biopsy device providing for electrosurgical cutting and coagulation by way of a catheter containing a cutting electrode which is moveable by manipulation of a core wire.
Another object of the invention is to utilize a rotatable, single-hinged moving element having mating electrodes for the cutting head.
Yet another object of the invention is to provide a biopsy device with a RF cutting/coagulating head on the distal end of a catheter, the head having a member reciprocably moveable relative to a member fixed to the catheter by utilizing a core wire running the length of the catheter.
Another object of the invention is to provide a bipolar electrode biopsy device having varying means for rotationally journaling the cutting head.